| Autor: |
Howell RE; Wyeth-Ayerst Research, Princeton, NJ 08543., Sickels BD, Weichman BM |
| Jazyk: |
angličtina |
| Zdroj: |
Agents and actions [Agents Actions] 1992 Nov; Vol. 37 (3-4), pp. 195-7. |
| DOI: |
10.1007/BF02028107 |
| Abstrakt: |
Chronic airway hyperreactivity is a hallmark feature of asthma, but animal models of airway hyperreactivity often utilize a single antigen challenge. Therefore, we compared the airway hyperreactivity produced by single and multiple antigen challenges in ovalbumin-sensitized guinea pigs. Significant (2-fold) leftward shifts in dose-response curves for i.v. methacholine- or LTD4-induced bronchoconstriction in anesthetized and ventilated animals occurred 24 h following a single ovalbumin challenge. This nonspecific airway hyperreactivity was prevented by pretreatment with ketotifen or dexamethasone. However, airway hyperreactivity was no greater 24 h following the last of 3 daily antigen challenges than after 1 challenge and was absent 72 h following one antigen challenge. These results raise concern over the similarity of antigen-induced airway hyperreactivity in guinea pigs to the chronic airway hyperreactivity in asthmatics. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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